Oaklynn Special School
- 20 Mayville Avenue, New Lynn, Auckland
OA Systems Ltd
- Level 6, 27 Gillies Avenue, Newmarket, Auckland
Obex Medical Ltd
- Level 1, AstraZeneca House, 303 Manukau Road, Epsom, Auckland
Auckland Obstetric Centre Limited
- Ground Floor, Birthcare Building, 20 Titoki Street, Parnell, Auckland
Oceandry Drysuits Ltd
- 25 Station Road, Wellsford
Oceanz Seafood Downtown
- Cnr Jellicoe & Daldy St, Westhaven, Auckland Central
OCG Consulting Ltd Auckland
- Level 8 ANZ Centre, 23-29 Albert Street, Auckland
OCS – Auckland
- Level 4, 26 Virginia Avenue, Eden Terrace, Auckland
OfficeMax Glenfield
- 93 Wairau Road, Glenfield, Auckland
Oikoumene Forest Ltd
- 197 Wishart Road, RD 2, Helensville, Auckland
Okra Espresso Lounge & Gallery
- 161 Sandringham Rd, Sandringham, Auckland
Omaha Bay Vineyard
- 189 Takatu Rd, Matakana